Ventilatory Constraint, Breathing Pattern and Ventilatory Responses in Obese Postmenopausal Women

Obesity Clinical Trial

Official title:

Ventilatory Constraint, Breathing Pattern and Ventilatory Responses in Obese Postmenopausal Women

Clinical Trial Details — Status: Completed

Administrative data

• NCT number: NCT01034098
• Other study ID #: 9461701144
• Status: Completed
• Phase: N/A
• First received: December 16, 2009
• Last updated: December 16, 2009
• Start date: December 2005
• Est. completion date: April 2007

Study information

• Verified date: December 2009
• Source: National Taiwan University Hospital
• Contact: n/a
• Is FDA regulated: No
• Health authority: Taiwan: Department of Health
• Study type: Observational

Clinical Trial Summary

The purpose of this study was to examine the dynamic lung volumes in obese post-menopausal women (without hormone replacement therapy) during exercise and their correlations with dyspnea.

Description:

Obesity-related changes in lung volumes have shown to affect breathing mechanisms. During exercise, altered breathing mechanisms increase potential for expiratory flow limitation and compromise exercise capacity. Estrogen and progesterone are potent respiratory stimulants, and their effects in the physiologic regulation of breathing are down-regulated after menopause. Therefore, we theorized that the combined obesity and reduced sex hormone levels after menopause work as a double jeopardy to cause mechanical ventilatory constraint which aggravates dyspnea sensation during exercise, and thus a reduction in exercise capacity. The purpose of this study was to exam the dynamic lung volumes in obese post-menopausal women (without hormone replacement therapy) during exercise and their correlations with dyspnea.

From doctoral referral and advertisement, 24 obese (BMI ≧ 27 kg/m2) and 26 lean post-menopausal women were recruited for the study. Pulmonary function and body composition were measured at rest. A maximal flow volume loop (MFVL) was obtained at baseline. All subjects then performed an incremental exercise test on a cycle ergometer with workload increasing 25 watts every 3 min. During exercise, at each workload, the tidal exercise FV loops were obtained and an inspiratory capacity (IC) maneuver was conducted to assess changes in end-expiratory lung volume (EELV) and end inspiratory lung volume (EILV). Dyspnea and leg fatigue were assessed using the Borg scale. Analysis of variance with repeated measurements was used to test the significance of the mean differences between the two groups during exercise. Linear regression analysis was used to determine whether changes in dynamic lung volumes during exercise were related to changes in Borg scores. Statistical significance was established at p<0.05.

Recruitment information / eligibility

• Status: Completed
• Enrollment: 50
• Est. completion date: April 2007
• Est. primary completion date: April 2007
• Accepts healthy volunteers: Accepts Healthy Volunteers
• Gender: Female
• Age group: 50 Years to 69 Years

Eligibility

Inclusion Criteria:

• Postmenopausal women (for at least 1 year)

• Age below 69 y/o

• Not receiving hormone replacement therapy

Exclusion Criteria:

• Cardiopulmonary disease

• Musculoskeletal disease affecting results of maximal exercise test

Study Design

Observational Model: Cohort, Time Perspective: Cross-Sectional

Related Conditions & MeSH terms

• Obesity
• Postmenopausal Women

Locations

Country	Name	City	State
Taiwan	School and Graduate Institute of Physical Therapy, National Taiwan University	Taipei

Sponsors (1)

Lead Sponsor	Collaborator
National Taiwan University Hospital

Country where clinical trial is conducted

Taiwan, 

Outcome

Type	Measure	Description	Time frame	Safety issue
Primary	Dynamic lung volume: end-expiratory lung volume (EELV), end-inspiratory lung volume (EILV)		At least 1 year post-menopause	Yes
Secondary	Pulmonary function		At least 1 year post-menopause	Yes
Secondary	Breathing pattern		At least 1 year post-menopause	Yes
Secondary	Ventilatory response		At least 1 year post-menopause	Yes
Secondary	Visual analog scale (VAS) for dyspnea and leg fatigue		At least 1 year post-menopause	Yes